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DOE announces NEPA exclusion for advanced reactors
The Department of Energy has announced that it is establishing a categorical exclusion for the application of National Environmental Policy Act (NEPA) procedures to the authorization, siting, construction, operation, reauthorization, and decommissioning of advanced nuclear reactors.
According to the DOE, this significant change, which goes into effect today, “is based on the experience of DOE and other federal agencies, current technologies, regulatory requirements, and accepted industry practice.”
Shin Chang, George H. Miley, Clifford E. Singer
Fusion Science and Technology | Volume 33 | Number 4 | July 1998 | Pages 387-397
Technical Paper | doi.org/10.13182/FST98-A39
Articles are hosted by Taylor and Francis Online.
The influence of controlled sawteeth on thermal helium exhaust is explored using the BALDUR 1½-dimensional transport code for an ARIES-I-type plasma. Sawteeth are shown to be useful for removing thermal helium from the central region to the outer region of a tokamak plasma. Outer region transport enhancement is found essential for removing the ash from the outer region. It is found that the optimal sawtooth period to give the minimum thermal helium level (or maximum fusion power) is several times larger than the fast alpha-particle slowing-down time for an ARIES-I-type driven plasma. With a sawtooth period of ~5 s and helium transport selectively enhanced by one order of magnitude relative to the diffusion of hydrogenic ions, the fusion power increases ~30% compared to the case without sawteeth/without enhancement. It is also found that sawteeth combined with outer region transport enhancement have the potential to advantageously reduce the helium concentration.